Ophthalmic test chart



L. L. MINCER OPHTHALMIC TEST CHART Original Filed Aug. 16, 1921 ill;

INVENTOR. LOU/5 4 1 1 (.QY BY %%5TTORNEY Patented Jan. 20, 1925.

PATENT FlQE.

LOUIS L. MINCER, OF ROCHESTER. NEW YORK.

OPHTHALMIC TEST CHART.

Application filed August 16, 1921, Serial No. 492,793. Renewed August18, 1924.

To all whom it may COHCGFIL.

Be it known that I, LOUIS L. Minoan, a citizen of the United States, andresident of Rochester, in the county of Monroe and State of New York,have invented certain new and useful Improvements in Ophthalmic TestCharts; and I do declare: the following to be afull, clear, and exactdescription of the same, taken in connection with the accompanyingdrawings, forming a part of this specification.

My invention relates to ophthalmic test charts of the kind used in theexamination of eyes for properly fitting spectacles or eye glasses, andhas for its principal object the construction of a chart which issimple, convenient to use, attractive inappearance, and which can bemanufactured economically. A further object of my invention is toprovide a chart in Which a test card can be readily inserted or removedtherefrom. A still further object of my invention is to provide a. testchart which is properly illuminated by means of electric lampsconveniently controlled by the operator. More specifically the object ofmy invention is to provide a test chart comprising a frame havingelectric lamps positioned at its sides and having a handle and a switchadjacent to the handle for controlling the electric lamps. To these andother ends my invention consists in certain improvements, arrangement,and combination of parts as will hereinafter more fully appear andparticularly pointed out in the claims at the end of this specification.

In the drawings:

Fig. 1 is a front elevation of an ophthalmic test chart constructedaccording to my invention,

Fig. 2 is a plan'view of the same, and

Fig. 3 is a section on the line 3-"--3 of Fig. 1.

Referring particularly to the drawings, my improved chart comprisesaframe 1 constructed of sheet metal and turned up or rolled forwardly atits side edges to fornr substantially cylindrical housings 2 and 3 openat their inner sides for a purpose presently to be described. At itslower edge, it has formed integral therewith, a tubular housing 4 openat its outer ends adjacent the lower ends of the housings 2 and 3 andalso having an opening 5 intermediate its ends. Thus constructed theframe 1 is substantially rectangular in form and neat in appearance.

Secured to its forward face by means of rivets or other suitablesecuring means is a rectangular frame 6, spaced from the front wall ofthe frame 1 and open or free from the frame 1 at its upper edge, as at7, to provide slot or pocket into which an ophthalmic test card may beconveniently inserted. \Vithin the housings 2 and 3 are providedelectric lamp sockets for the lamps 8 and the inner walls of saidhousings may be highly polished or silvered in order to direct orreflect the light from the lamps 8 through the open sides of thehousings upon the front face of the frame 1 or the card exposed throughthe frame 7 The electric conductors connected with the lamps 8 are drawnthrough the tubular member 4 and through the opening 5 where they areconnected with a suitable switch 10.

The switch 10 is mounted in a tubular member llsecured by rivets orother suit able means to the rear face of the frame 1 in position tocommunicate with the opening 5 in the member 4 and open at its lowerend. The tubular member 11 is provided with openings in its front andrear walls through which buttons 12 and 13 for controlling the switch 10slideably project. Connected with the outer end of the switch are theconductors 1 1 leading to any suit able source of electric current.

For convenience in using the chart, I provide the same with a suitablehandle 15, said handle is tubular so that the conductors 14 may extendtherethrough. At its upper end the handle 15 is slightly reduced indiameter so that it may be conveniently inserted in the outer end of thetubular member 11 and secured in position by means of a screw insertedin the tapped opening 16 in the member 11 for engagement with thehandle. It will be noted that by this construction the handle may bereadily detached from the chart or secured thereto when it is desired touse the chart as a hand instrument. In order to improve the appearanceof the chart extensions 17 and 18 extending laterally of the tubularmernber 11 may be provlded and may be conveniently secured to the rearof the handle adjacent its upper end to be removed there- With or, ifdesired, they may be permanently secured to the chart by any suitable orconvenient means.

It Willbe noted 1 that by the arrangement of the lamps Within thetubular reflectors, direct rays of light are prevented from reaching theeyes of 'the patient and the light from the lamps may be uniformlydistributed over the front face of the test card. a

I have also provided means for supporting a close muscle chart formuscular-tests, between the 'fr'eeedges of the reflectors 2 and 3. Saidmeans 'comprisesthe parts '19 and 20 integral With the reflectors 2 and8 and having card retalnln'g extensions.

I-Iaving described my invention What 1 claimand desire to'secure'byLetters Patent 15: V

1. A test chart holder comprising a substantially rectangular frame,adapted to hold a test card, a lamp supported at each sideof said frame,a switch supported on said frame intermediate said lamps, conside ofsaid frame, a reflector associated with each of said lamps and adaptedto concentrate the light of the lamps on the test card, and meansforsupporting a muscle test chart between said reflectors and spaced fromthe test card.

LOUIS L. MINOER.

